THE Maritime Industry Authority (Marina) is investigating the alleged suspicious activities of Chinese dredgers operating in Manila Bay that were raised by the National Coast Watch Center (NCWC), an interagency maritime surveillance and coordinated response facility.

'Based on the special report of NCWC, several foreign vessels were allegedly engaged in suspicious activities and were observed to be operating outside their approved areas of operation as against the issued special permit by Marina,' the maritime authority said in a report.